The Experts below are selected from a list of 918 Experts worldwide ranked by ideXlab platform

S. Bjørnson - One of the best experts on this subject based on the ideXlab platform.

  • effects of microsporidiosis and food availability on the two spotted lady beetle adalia bipunctata l and convergent lady beetle Hippodamia convergens guerin meneville
    Journal of Invertebrate Pathology, 2019
    Co-Authors: T. Steele, S. Bjørnson
    Abstract:

    Abstract Two species of microsporidia have been described from lady beetles that are commercially available for biological control: Nosema adaliae from the two-spotted lady beetle, Adalia bipunctata L., and Tubulinosema Hippodamiae from the convergent lady beetle, Hippodamia convergens Guerin-Meneville. These pathogens delay larval development under controlled conditions, but little is known regarding the effects that microsporidia cause when their hosts are subjected to stressful conditions that are often experienced in nature. In this study, the combined effects of microsporidiosis (N. adaliae on A. bipunctata and T. Hippodamiae on H. convergens) and irregular food availability were observed on host fitness (larval development and mortality, sex ratios, and adult morphometrics). For each beetle species, 24 h-old larvae were provided either an uninfected or microsporidia-infected conspecific egg. After the egg was eaten, some larvae were provided an abundance of aphids daily, whereas others were provided aphids on an irregular basis. Development was delayed significantly for larvae that consumed a microsporidia-infected egg, and for those fed irregularly. For A. bipunctata, a significant interaction was observed between infection status and food availability. This suggests that N. adaliae-infected A. bipunctata larvae that have an irregular supply of aphids undergo further developmental delays than those with a generous food supply. This interaction was not observed for T. Hippodamiae-infected H. convergens. For both species, larval mortality and sex ratios did not differ significantly, regardless of infection status or food availability. Adults that were fed daily as larvae were significantly larger than those fed irregularly. However, the elytra of N. adaliae-infected A. bipunctata were significantly larger than the elytra of their uninfected cohorts, and T. Hippodamiae-infected H. convergens had wider pronota and head capsules than uninfected H. convergens. Because N. adaliae and T. Hippodamiae prolong larval development of their respective hosts under controlled conditions, one would expect these pathogens to cause more profound effects when their hosts experience stressful conditions. The results from this study indicate that this was the case for A. bipunctata, but not for H. convergens.

  • The convergent lady beetle, Hippodamia convergens Guérin-Méneville and its endoparasitoid Dinocampus coccinellae (Schrank): the effect of a microsporidium on parasitoid development and host preference.
    Journal of invertebrate pathology, 2013
    Co-Authors: T. Saito, S. Bjørnson
    Abstract:

    Convergent lady beetles, Hippodamia convergens Guerin-Meneville are host to the braconid endoparasitoid, Dinocampus coccinellae (Schrank) and the microsporidian pathogen, Tubulinosema Hippodamiae. The interrelationship between the endoparasitoid and the pathogen in H. convergens adults under laboratory conditions was examined by quantifying the effect of microsporidiosis on D. coccinellae development and host preference. Uninfected wasps were provided either uninfected or T. Hippodamiae-infected beetles as hosts and the development of their progeny was observed over 30 days. The duration of endoparasitoid development from egg deposition in the host until adult eclosion for D. coccinellae did not differ significantly, regardless of the infection status of the host beetle. All wasp progeny that developed within, and emerged from, T. Hippodamiae-infected beetles were infected with the microsporidian pathogen (n = 48; 100% transmission). Infected D. coccinellae adults were also provided either uninfected or T. Hippodamiae infected host beetles so that the development of their progeny could be assessed over 30 days. Endoparasitoid development did not differ significantly; however, a significantly greater proportion of beetles stung by microsporidia-infected wasps did not contain an endoparasitoid larva when dissected at the end of the 30-day trial when compared to those stung by uninfected wasps. This suggests that the pathogen may reduce wasp fecundity or egg viability. Examination of paraffin-embedded D. coccinellae adult tissues revealed an extensive microsporidian infection throughout all major organs and tissues with exception of the ovary. During host choice trials, uninfected and microsporidia-infected D. coccinellae adults pursued, took an ovipositional stance, and attacked uninfected beetles more often than microsporidia-infected hosts but these observations did not differ significantly (P > 0.05).

  • ultrastructure and molecular characterization of a microsporidium tubulinosema Hippodamiae from the convergent lady beetle Hippodamia convergens guerin meneville
    Journal of Invertebrate Pathology, 2011
    Co-Authors: S. Bjørnson, T. Saito, H Wang
    Abstract:

    Abstract Hippodamia convergens, the convergent lady beetle, is available for aphid control in home gardens and in commercial food production systems throughout the United States and Canada. Beetles received from commercial insectaries for biological control are occasionally infected with a microsporidium. The objective of this study was to describe the pathogen by means of ultrastructure, molecular characterization and tissue pathology. All stages of the microsporidium were in direct contact with the host cell cytoplasm. Early developmental stages were proximal to mature spores and both were observed throughout the tissue sections that were examined. Merogony resulted from binary fission. Early-stage sporoblasts were surrounded by a highly convoluted plasma membrane and contained an electron-dense cytoplasm and diplokaryon. Ovoid to elongated late-stage sporoblasts were surrounded by a relatively complete spore wall. The polar filament, polaroplast, and anchoring disk were readily observed within the cell cytoplasm. Mature spores were typical of terrestrial microsporidia, with a thickened endospore surrounded by a thin exospore. Spores contained well-defined internal structures, including a diplokaryon, lamellar polaroplast and a slightly anisofilar polar filament with 10–14 coils arranged in a single or double row. A prominent indentation was evident at the apical end of the spore wall proximal to the anchoring disk. Aberrant spores were also observed. These had a fully developed endospore and exospore but lacked any discernable internal spore structures, and were, instead, filled with lamellar or vesicular structures. Typical and aberrant spores measured 3.58 ± 0.2 × 2.06 ± 0.2 μm (n = 10) and 3.38 ± 0.8 × 2.13 ± 0.2 μm (n = 10), respectively. Spores were observed in longitudinal muscle surrounding the midgut and within the fat body, Malpighian tubules, pyloric valve epithelium, ventral nerve cord ganglia, muscles and ovaries. The hindgut epithelium was often infected but the connective tissues were rarely invaded. The life cycle and pathology of the microsporidium bears some resemblance to Nosema Hippodamiae, the only microsporidium reported from H. convergens by Lipa and Steinhaus in 1959. Molecular characterization of the pathogen genomic DNA revealed that it is 99% similar to Tubulinosema acridophagus and T. ratisbonensis, two pathogens that infect Drosophila melanogaster and 98% similar to T. kingi from D. willistoni. Based on similarities in pathogen ultrastructure and the molecular information gained during this study, we propose that the microsporidium in H. convergens be given the name Tubulinosema Hippodamiae.

  • effects of a microsporidium from the convergent lady beetle Hippodamia convergens guerin meneville coleoptera coccinellidae on three non target coccinellids
    Journal of Invertebrate Pathology, 2008
    Co-Authors: T. Saito, S. Bjørnson
    Abstract:

    Abstract A microsporidium from Hippodamia convergens was transmitted horizontally to three non-target coccinellid hosts (Adalia bipunctata L., Coccinella septempunctata L. and Harmonia axyridis Pallas) under laboratory conditions. For all species examined, microsporidia-infected larvae took significantly longer to develop than did uninfected larvae but the microsporidium had no effect on larval mortality. Adult sex ratios of uninfected and microsporidia-infected adults were about 1:1 (♀:♂) and did not differ significantly. At the end of a 90-day trial, microsporidia-infected H. convergens produced significantly fewer eggs and did not live as long as uninfected individuals. Differences in fecundity and longevity were not observed for the three non-target coccinellids that were examined. Mean spore counts from smear preparations of microsporidia-infected A. bipunctata did not differ significantly from H. convergens, suggesting that A. bipunctata (a native coccinellid) is a suitable host for the microsporidium but infection was lighter in C. septempunctata and H. axyridis (introduced species). Vertical transmission of the pathogen was observed during the 90-day trial by examining eggs and larvae that were produced by microsporidia-infected adults. For all species examined, 100% vertical transmission of the pathogen was eventually observed. Three eugregarines were found in two adult A. bipunctata: Gregarine A trophozoites are similar in size to those of Gregarina katherina Watson (described earlier from Coccinella spp.), Gregarine B trophozoites are similar in size to those of Gregarine A but are morphology distinct, and Gregarine C trophozoites are similar in size to G. barbarara Watson (described earlier from A. bipunctata).

  • natural enemies of the convergent lady beetle Hippodamia convergens guerin meneville their inadvertent importation and potential significance for augmentative biological control
    Biological Control, 2008
    Co-Authors: S. Bjørnson
    Abstract:

    Abstract Each year, Hippodamia convergens adults are collected from their overwintering sites in California and made commercially available for aphid control in agriculture and in home gardens. This study examines the prevalence of natural enemies encountered in commercially available H. convergens from three commercial suppliers. Microsporidia were detected in individuals from 13 of 22 shipments (0.9% prevalence, range 0–3%). Spore dimensions (3.9 ± 0.1 × 2.5 ± 0.1 μm; n  = 50) were similar to those of Nosema Hippodamiae (reported previously from H. convergens ), Nosema tracheophila and Nosema coccinellae (reported from other coccinellids). Because H. convergens are sold in large quantities, thousands of microsporidia-infected beetles could be released each time H. convergens are used. Three distinct eugregarines were observed in H. convergens (0.2% prevalence) but none were similar in size to Gregarina barbarara , the only eugregarine reported from H. convergens. Although eugregarines are usually considered as mutualist symbionts or weak pathogens, the relationship between eugregarines and coccinellids is not fully understood. The hymenopteran parasitoid, Dinocampus coccinellae , was found in beetles from all shipments (8% mean parasitism, range: 3–15%). Significantly more females were parasitized than males. The importation and release of D. coccinellae undermine the success of biological control programs and may artificially increase the number of parasitoids in an area where H. convergens are released. Verticillium sp. (2% prevalence; range: 0–9%) was also observed but its role is unknown. Beetle quantities and sex ratios were also assessed.

Jiménez Vela, Enma Emperatriz - One of the best experts on this subject based on the ideXlab platform.

  • Influencia de la Hippodamia convergens en el control biológico de Myzus persicae presente en el Solanum lycopersicum a condiciones de invernadero
    'Universidad Cesar Vallejo', 2019
    Co-Authors: Chinchayhuara Capa, Rosario Kelly, Jiménez Vela, Enma Emperatriz
    Abstract:

    El control biológico busca contribuir con una alternativa de solución ante la infestación de plagas en los cultivos, reducir los efectos negativos que en gran mayoría disminuye la producción y la aplicación excesiva de plaguicidas, siendo los químicos los que contaminan el suelo, agua y aire. El objetivo principal de la investigación fue determinar la influencia de la Hippodamia convergens “mariquita” en el control biológico de Myzus persicae “pulgón” presente en el Solanum lycopersicum “tomate “a condiciones de invernadero, como enemigo natural se utilizó a los cuatro estadíos larvales (I,II,III,VI) de la Hippodamia convergens “mariquita” durante 31 días, se hizo el conteo del número de Myzus persicae “pulgón” depredados, utilizando el método de la aguja, las larvas fueron criadas desde la reproducción, mientras que los Myzus persicae “pulgón” fueron recolectado de un huerto de Solanum lycopersicum “tomate” ubicados en distrito El Porvenir –Trujillo. El diseño fue experimental factorial con medidas repetidas, un grupo control, de tipo aplicada – cuantitativa. Los grupos experimentales fueron cuatro tratamientos con grupo control T0:0/1500; T1:3/1500; T2:4/1500; T3:9/1500 (estadíos de Hippodamia converges “mariquita” versus el Myzus persicae “pulgón” ).Según la prueba estadística de comparaciones múltiples de Duncan fue T3:9/1500 el más eficiente a su vez con un promedio de 1476 Myzus persicae “pulgón” depredados, con un porcentaje de control del 98,31 % seguido del T2 :6/1500 con un promedio de 962 Myzus persicae “pulgón” depredados con porcentaje de control de 64.17 % .También el porcentaje de control por estadío fue el IV con 51.47 % en el T3.Finalmente los aspectos etológicos de las larvas por estadío tienen diferente longitud de crecimiento con 2 mm hasta 8 mm ,siendo el III y IV estadío más depredadores contra la plaga que ataca a la planta de solanum lycopersicum “tomate”

  • Influencia de la Hippodamia convergens en el control biológico de Myzus persicae presente en el Solanum lycopersicum a condiciones de invernadero
    'Universidad Cesar Vallejo', 2019
    Co-Authors: Chinchayhuara Capa, Rosario Kelly, Jiménez Vela, Enma Emperatriz
    Abstract:

    TesisTrujilloEscuela Académico Profesional de Ingeniería AmbientalCalidad y Gestión de Recursos NaturalesEl control biológico busca contribuir con una alternativa de solución ante la infestación de plagas en los cultivos, reducir los efectos negativos que en gran mayoría disminuye la producción y la aplicación excesiva de plaguicidas, siendo los químicos los que contaminan el suelo, agua y aire. El objetivo principal de la investigación fue determinar la influencia de la Hippodamia convergens “mariquita” en el control biológico de Myzus persicae “pulgón” presente en el Solanum lycopersicum “tomate “a condiciones de invernadero, como enemigo natural se utilizó a los cuatro estadíos larvales (I,II,III,VI) de la Hippodamia convergens “mariquita” durante 31 días, se hizo el conteo del número de Myzus persicae “pulgón” depredados, utilizando el método de la aguja, las larvas fueron criadas desde la reproducción, mientras que los Myzus persicae “pulgón” fueron recolectado de un huerto de Solanum lycopersicum “tomate” ubicados en distrito El Porvenir –Trujillo. El diseño fue experimental factorial con medidas repetidas, un grupo control, de tipo aplicada – cuantitativa. Los grupos experimentales fueron cuatro tratamientos con grupo control T0:0/1500; T1:3/1500; T2:4/1500; T3:9/1500 (estadíos de Hippodamia converges “mariquita” versus el Myzus persicae “pulgón” ).Según la prueba estadística de comparaciones múltiples de Duncan fue T3:9/1500 el más eficiente a su vez con un promedio de 1476 Myzus persicae “pulgón” depredados, con un porcentaje de control del 98,31 % seguido del T2 :6/1500 con un promedio de 962 Myzus persicae “pulgón” depredados con porcentaje de control de 64.17 % .También el porcentaje de control por estadío fue el IV con 51.47 % en el T3.Finalmente los aspectos etológicos de las larvas por estadío tienen diferente longitud de crecimiento con 2 mm hasta 8 mm ,siendo el III y IV estadío más depredadores contra la plaga que ataca a la planta de solanum lycopersicum “tomate”

T. Saito - One of the best experts on this subject based on the ideXlab platform.

  • The convergent lady beetle, Hippodamia convergens Guérin-Méneville and its endoparasitoid Dinocampus coccinellae (Schrank): the effect of a microsporidium on parasitoid development and host preference.
    Journal of invertebrate pathology, 2013
    Co-Authors: T. Saito, S. Bjørnson
    Abstract:

    Convergent lady beetles, Hippodamia convergens Guerin-Meneville are host to the braconid endoparasitoid, Dinocampus coccinellae (Schrank) and the microsporidian pathogen, Tubulinosema Hippodamiae. The interrelationship between the endoparasitoid and the pathogen in H. convergens adults under laboratory conditions was examined by quantifying the effect of microsporidiosis on D. coccinellae development and host preference. Uninfected wasps were provided either uninfected or T. Hippodamiae-infected beetles as hosts and the development of their progeny was observed over 30 days. The duration of endoparasitoid development from egg deposition in the host until adult eclosion for D. coccinellae did not differ significantly, regardless of the infection status of the host beetle. All wasp progeny that developed within, and emerged from, T. Hippodamiae-infected beetles were infected with the microsporidian pathogen (n = 48; 100% transmission). Infected D. coccinellae adults were also provided either uninfected or T. Hippodamiae infected host beetles so that the development of their progeny could be assessed over 30 days. Endoparasitoid development did not differ significantly; however, a significantly greater proportion of beetles stung by microsporidia-infected wasps did not contain an endoparasitoid larva when dissected at the end of the 30-day trial when compared to those stung by uninfected wasps. This suggests that the pathogen may reduce wasp fecundity or egg viability. Examination of paraffin-embedded D. coccinellae adult tissues revealed an extensive microsporidian infection throughout all major organs and tissues with exception of the ovary. During host choice trials, uninfected and microsporidia-infected D. coccinellae adults pursued, took an ovipositional stance, and attacked uninfected beetles more often than microsporidia-infected hosts but these observations did not differ significantly (P > 0.05).

  • ultrastructure and molecular characterization of a microsporidium tubulinosema Hippodamiae from the convergent lady beetle Hippodamia convergens guerin meneville
    Journal of Invertebrate Pathology, 2011
    Co-Authors: S. Bjørnson, T. Saito, H Wang
    Abstract:

    Abstract Hippodamia convergens, the convergent lady beetle, is available for aphid control in home gardens and in commercial food production systems throughout the United States and Canada. Beetles received from commercial insectaries for biological control are occasionally infected with a microsporidium. The objective of this study was to describe the pathogen by means of ultrastructure, molecular characterization and tissue pathology. All stages of the microsporidium were in direct contact with the host cell cytoplasm. Early developmental stages were proximal to mature spores and both were observed throughout the tissue sections that were examined. Merogony resulted from binary fission. Early-stage sporoblasts were surrounded by a highly convoluted plasma membrane and contained an electron-dense cytoplasm and diplokaryon. Ovoid to elongated late-stage sporoblasts were surrounded by a relatively complete spore wall. The polar filament, polaroplast, and anchoring disk were readily observed within the cell cytoplasm. Mature spores were typical of terrestrial microsporidia, with a thickened endospore surrounded by a thin exospore. Spores contained well-defined internal structures, including a diplokaryon, lamellar polaroplast and a slightly anisofilar polar filament with 10–14 coils arranged in a single or double row. A prominent indentation was evident at the apical end of the spore wall proximal to the anchoring disk. Aberrant spores were also observed. These had a fully developed endospore and exospore but lacked any discernable internal spore structures, and were, instead, filled with lamellar or vesicular structures. Typical and aberrant spores measured 3.58 ± 0.2 × 2.06 ± 0.2 μm (n = 10) and 3.38 ± 0.8 × 2.13 ± 0.2 μm (n = 10), respectively. Spores were observed in longitudinal muscle surrounding the midgut and within the fat body, Malpighian tubules, pyloric valve epithelium, ventral nerve cord ganglia, muscles and ovaries. The hindgut epithelium was often infected but the connective tissues were rarely invaded. The life cycle and pathology of the microsporidium bears some resemblance to Nosema Hippodamiae, the only microsporidium reported from H. convergens by Lipa and Steinhaus in 1959. Molecular characterization of the pathogen genomic DNA revealed that it is 99% similar to Tubulinosema acridophagus and T. ratisbonensis, two pathogens that infect Drosophila melanogaster and 98% similar to T. kingi from D. willistoni. Based on similarities in pathogen ultrastructure and the molecular information gained during this study, we propose that the microsporidium in H. convergens be given the name Tubulinosema Hippodamiae.

  • effects of a microsporidium from the convergent lady beetle Hippodamia convergens guerin meneville coleoptera coccinellidae on three non target coccinellids
    Journal of Invertebrate Pathology, 2008
    Co-Authors: T. Saito, S. Bjørnson
    Abstract:

    Abstract A microsporidium from Hippodamia convergens was transmitted horizontally to three non-target coccinellid hosts (Adalia bipunctata L., Coccinella septempunctata L. and Harmonia axyridis Pallas) under laboratory conditions. For all species examined, microsporidia-infected larvae took significantly longer to develop than did uninfected larvae but the microsporidium had no effect on larval mortality. Adult sex ratios of uninfected and microsporidia-infected adults were about 1:1 (♀:♂) and did not differ significantly. At the end of a 90-day trial, microsporidia-infected H. convergens produced significantly fewer eggs and did not live as long as uninfected individuals. Differences in fecundity and longevity were not observed for the three non-target coccinellids that were examined. Mean spore counts from smear preparations of microsporidia-infected A. bipunctata did not differ significantly from H. convergens, suggesting that A. bipunctata (a native coccinellid) is a suitable host for the microsporidium but infection was lighter in C. septempunctata and H. axyridis (introduced species). Vertical transmission of the pathogen was observed during the 90-day trial by examining eggs and larvae that were produced by microsporidia-infected adults. For all species examined, 100% vertical transmission of the pathogen was eventually observed. Three eugregarines were found in two adult A. bipunctata: Gregarine A trophozoites are similar in size to those of Gregarina katherina Watson (described earlier from Coccinella spp.), Gregarine B trophozoites are similar in size to those of Gregarine A but are morphology distinct, and Gregarine C trophozoites are similar in size to G. barbarara Watson (described earlier from A. bipunctata).

  • horizontal transmission of a microsporidium from the convergent lady beetle Hippodamia convergens guerin meneville coleoptera coccinellidae to three coccinellid species of nova scotia
    Biological Control, 2006
    Co-Authors: T. Saito, S. Bjørnson
    Abstract:

    Abstract Convergent lady beetles, Hippodamia convergens Guerin-Meneville, are a popular choice for aphid control in North America. An unidentified microsporidium was found in H. convergens adults that were purchased from a commercial insectary in 2004. This study examined egg cannibalism and egg predation as a means of horizontal transmission of the unidentified microsporidium among H. convergens larvae and three coccinellid species found in Nova Scotia: Coccinella septempunctata (seven-spotted lady beetle), C. trifasciata perplexa (three-banded lady beetle), and Harmonia axyridis (multicolored Asian lady beetle). The microsporidium was transmitted with 100% efficiency when first instars fed on microsporidia-infected eggs. Mean spore count data from smear preparations of infected beetles suggest that the infection was as heavy in C. trifasciata perplexa (a native coccinellid) (11.2 ± 0.96 spores/100 μm 2 ) as it was in H. convergens (the natural host) (12.8 ± 1.16) but lighter in the introduced species C. septempunctata (7.5 ± 0.65) and H. axyridis (0.8 ± 0.11). For all of the beetle species examined, larval development was significantly longer for microsporidia-infected individuals than for their uninfected cohorts. The microsporidium had no effect on larval mortality. Based on the results of this study, field-collected H. convergens should be examined for microsporidia and uninfected individuals should be used to rear individuals for release in biological control programs. However, this is unlikely to happen because H. convergens are relatively easy and inexpensive to collect from their overwintering sites for redistribution.

Chinchayhuara Capa, Rosario Kelly - One of the best experts on this subject based on the ideXlab platform.

  • Influencia de la Hippodamia convergens en el control biológico de Myzus persicae presente en el Solanum lycopersicum a condiciones de invernadero
    'Universidad Cesar Vallejo', 2019
    Co-Authors: Chinchayhuara Capa, Rosario Kelly, Jiménez Vela, Enma Emperatriz
    Abstract:

    El control biológico busca contribuir con una alternativa de solución ante la infestación de plagas en los cultivos, reducir los efectos negativos que en gran mayoría disminuye la producción y la aplicación excesiva de plaguicidas, siendo los químicos los que contaminan el suelo, agua y aire. El objetivo principal de la investigación fue determinar la influencia de la Hippodamia convergens “mariquita” en el control biológico de Myzus persicae “pulgón” presente en el Solanum lycopersicum “tomate “a condiciones de invernadero, como enemigo natural se utilizó a los cuatro estadíos larvales (I,II,III,VI) de la Hippodamia convergens “mariquita” durante 31 días, se hizo el conteo del número de Myzus persicae “pulgón” depredados, utilizando el método de la aguja, las larvas fueron criadas desde la reproducción, mientras que los Myzus persicae “pulgón” fueron recolectado de un huerto de Solanum lycopersicum “tomate” ubicados en distrito El Porvenir –Trujillo. El diseño fue experimental factorial con medidas repetidas, un grupo control, de tipo aplicada – cuantitativa. Los grupos experimentales fueron cuatro tratamientos con grupo control T0:0/1500; T1:3/1500; T2:4/1500; T3:9/1500 (estadíos de Hippodamia converges “mariquita” versus el Myzus persicae “pulgón” ).Según la prueba estadística de comparaciones múltiples de Duncan fue T3:9/1500 el más eficiente a su vez con un promedio de 1476 Myzus persicae “pulgón” depredados, con un porcentaje de control del 98,31 % seguido del T2 :6/1500 con un promedio de 962 Myzus persicae “pulgón” depredados con porcentaje de control de 64.17 % .También el porcentaje de control por estadío fue el IV con 51.47 % en el T3.Finalmente los aspectos etológicos de las larvas por estadío tienen diferente longitud de crecimiento con 2 mm hasta 8 mm ,siendo el III y IV estadío más depredadores contra la plaga que ataca a la planta de solanum lycopersicum “tomate”

  • Influencia de la Hippodamia convergens en el control biológico de Myzus persicae presente en el Solanum lycopersicum a condiciones de invernadero
    'Universidad Cesar Vallejo', 2019
    Co-Authors: Chinchayhuara Capa, Rosario Kelly, Jiménez Vela, Enma Emperatriz
    Abstract:

    TesisTrujilloEscuela Académico Profesional de Ingeniería AmbientalCalidad y Gestión de Recursos NaturalesEl control biológico busca contribuir con una alternativa de solución ante la infestación de plagas en los cultivos, reducir los efectos negativos que en gran mayoría disminuye la producción y la aplicación excesiva de plaguicidas, siendo los químicos los que contaminan el suelo, agua y aire. El objetivo principal de la investigación fue determinar la influencia de la Hippodamia convergens “mariquita” en el control biológico de Myzus persicae “pulgón” presente en el Solanum lycopersicum “tomate “a condiciones de invernadero, como enemigo natural se utilizó a los cuatro estadíos larvales (I,II,III,VI) de la Hippodamia convergens “mariquita” durante 31 días, se hizo el conteo del número de Myzus persicae “pulgón” depredados, utilizando el método de la aguja, las larvas fueron criadas desde la reproducción, mientras que los Myzus persicae “pulgón” fueron recolectado de un huerto de Solanum lycopersicum “tomate” ubicados en distrito El Porvenir –Trujillo. El diseño fue experimental factorial con medidas repetidas, un grupo control, de tipo aplicada – cuantitativa. Los grupos experimentales fueron cuatro tratamientos con grupo control T0:0/1500; T1:3/1500; T2:4/1500; T3:9/1500 (estadíos de Hippodamia converges “mariquita” versus el Myzus persicae “pulgón” ).Según la prueba estadística de comparaciones múltiples de Duncan fue T3:9/1500 el más eficiente a su vez con un promedio de 1476 Myzus persicae “pulgón” depredados, con un porcentaje de control del 98,31 % seguido del T2 :6/1500 con un promedio de 962 Myzus persicae “pulgón” depredados con porcentaje de control de 64.17 % .También el porcentaje de control por estadío fue el IV con 51.47 % en el T3.Finalmente los aspectos etológicos de las larvas por estadío tienen diferente longitud de crecimiento con 2 mm hasta 8 mm ,siendo el III y IV estadío más depredadores contra la plaga que ataca a la planta de solanum lycopersicum “tomate”

Jorge B. Torres - One of the best experts on this subject based on the ideXlab platform.

  • High Concentrations of Chlorantraniliprole Reduce Its Compatibility with a Key Predator, Hippodamia convergens (Coleoptera: Coccinellidae).
    Journal of Economic Entomology, 2017
    Co-Authors: Paulo R. R. Barbosa, J P Michaud, Jorge B. Torres, A R S Rodrigues
    Abstract:

    Diamides are a novel insecticide group that act by disrupting insect muscle contraction. Recommended field rates (FRs) vary greatly among target pests and cropping systems, leading to variable risks for non-target organisms. We evaluated the toxicity of chlorantraniliprole to the predator Hippodamia convergens Guerin-Meneville (Coleoptera: Coccinellidae) by exposure to residues, topical application, and consumption of contaminated food. We also estimated lethal concentrations (LCs) of chlorantraniliprole in two target pests, cotton leafworm, Alabama argillacea (Hubner) (Lepidoptera: Erebidae), and tobacco budworm, Chloridea virescens (F.) (Lepidoptera: Noctuidae), by exposing larvae to treated cotton, Gossypium hirsutum L., leaves and assessed residual activity at various intervals after application to cotton plants. Exposure to dried residues and ingestion of treated moth eggs resulted in similar toxicity to H. convergens, whereas topical application was a less toxic route of exposure. Regardless of exposure route, the LC50s and LC90s obtained for H. convergens were higher than those calculated for the pests. Residues at the upper limit of the LC90 for C. virescens remained effective against this pest for up to 16 d, while exhibiting minor impacts on H. convergens. In contrast, the FR concentration of C. virescens caused significant mortality in H. convergens. The results suggest that the current FR for C. virescens is too high to be safe for H. convergens, and given the LCs observed for this pest in the present study, trials to explore the potential efficacy of lower FRs are justified. Depending on the concentration and route of exposure, this insecticide has the potential to be compatible with H. convergens.

  • Relative Toxicity of Two Aphicides to Hippodamia convergens (Coleoptera: Coccinellidae): Implications for Integrated Management of Sugarcane Aphid, Melanaphis sacchari (Hemiptera: Aphididae).
    Journal of economic entomology, 2017
    Co-Authors: Felipe Colares, J P Michaud, Clint L. Bain, Jorge B. Torres
    Abstract:

    Flupyradifurone and sulfoxaflor present novel insecticide chemistries with particular efficacy against aphids, and the recent emergence of sugarcane aphid, Melanaphis sacchari (Zehntner), as a pest of sorghum in the United States has resulted in their widespread use. We examined their toxicity to Hippodamia convergens Guerin-Meneville, an important aphid biocontrol agent. We exposed beetles to topical applications of the field rate (FR) of these insecticides, fed them contaminated food (eggs of Ephestia kuehniella Zeller), and gave first-instar larvae 24-h exposures to leaf residues. More than half of fourth-instar larvae receiving topical applications of sulfoxaflor at FR survived, whereas flupyradifurone at 0.1× FR caused 90% mortality. Adults survived topical treatments better than larvae and without measurable mortality, except flupyradifurone at FR, which killed more than 80% of beetles. Survivors of all treatments had fertility similar to controls, whether treated as larvae or adults. Ingestion of contaminated food caused significant mortality in all treatments (15-40% for adults and 55-85% for larvae), with no significant differences between insecticides at FR. Leaf residues of sulfoxaflor at 1.0 and 2.0× FR caused approximately 60 and 80% mortality of first instars, respectively, whereas flupyradifurone at 0.1 and 1.0× FR caused > 90% mortality. Although sulfoxaflor was less toxic to H. convergens than flupyradifurone, the tested FR of flupyradifurone has now been reduced by half. We conclude that neither insecticide appears as toxic as other nicotinic acetylcholine receptor agonists, and that both materials are compatible with integrated pest management programs for M. sacchari.

  • Dual resistance to lambda-cyhalothrin and dicrotophos in Hippodamia convergens (Coleoptera: Coccinellidae).
    Chemosphere, 2016
    Co-Authors: Paulo R. R. Barbosa, J P Michaud, Agna R.s. Rodrigues, Jorge B. Torres
    Abstract:

    Insecticide resistance is usually associated with pests, but may also evolve in natural enemies. In this study, adult beetles of three distinct North American populations of Hippodamia convergens Guerin-Meneville, and the progeny of reciprocal crosses between the resistant and most susceptible population, were treated topically with varying concentrations of lambda-cyhalothrin and dicrotophos. In addition, the LD50s of both insecticides were applied in combination to resistant individuals. The developmental and reproductive performance of each population was assessed in the absence of insecticide exposure to compare baseline fitness. California and Kansas populations were susceptible to both materials, whereas Georgia (GA) beetles exhibited a resistance ratio (RR50) of 158 to lambda-cyhalothrin and 530 to dicrotophos. Inheritance of lambda-cyhalothrin resistance was X-linked, whereas inheritance of dicrotophos resistance was autosomal. Mortality of resistant beetles treated with a mixture of LD50s of both materials was twice that of those treated with lambda-cyhalothrin alone, but not significantly different from those receiving dicrotophos alone. Life history parameters were largely similar among populations, except that Georgia beetles had higher egg fertility relative to susceptible populations. We conclude that the high levels of resistance to lambda-cyhalothrin and dicrotophos in Georgia beetles reflect heavy loads of these insecticides in local environments, most likely the large acreage under intensive cotton cultivation.

  • pyrethroid resistance and its inheritance in a field population of Hippodamia convergens guerin meneville coleoptera coccinellidae
    Pesticide Biochemistry and Physiology, 2013
    Co-Authors: Agna R.s. Rodrigues, Jorge B. Torres, John R Ruberson, Herbert A A Siqueira, Jeffrey G Scott
    Abstract:

    Abstract The convergent lady beetle (CLB), Hippodamia convergens (Guerin-Meneville), a species widely distributed and used in biological control, has exhibited high survival under field and laboratory conditions when treated with field rates of the pyrethroid λ-cyhalothrin, a highly unusual phenomenon for a natural enemy. This work investigated and characterized the phenomenon of pyrethroid resistance in a population of this species collected in Georgia, USA. The mechanism and level of resistance were evaluated by treating parental populations with λ-cyhalothrin ± piperonyl butoxide (PBO). The inheritance bioassay utilized parental crosses and backcrosses between parental populations to obtain testable progenies. Adult beetles from populations and progenies were topically treated with different doses of λ-cyhalothrin (technical grade) to calculate knockdown (KD) and lethal (LD) doses, and to investigate the dominance based on a single dose and whether resistance is autosomal and monogenic (null hypothesis). Genetic variation in the parental populations was examined by applying a discriminating dose for resistant individuals (0.5 g/L). The data indicate that resistance is due to at least two factors: knockdown resistance and enzymatic detoxification of the insecticide. The knockdown effect is recessive and linked to the X-chromosome. Variability in proportions of individuals within families dying following knockdown indicated genetic variation in the resistant population . Further studies should be done to investigate the role of sex linked inheritance of resistance in the species and interactions of the various mechanisms involved in resistance.